1. Field of the Invention
The present invention relates generally to the field of scuba diving equipment and more particularly to a ball and socket swivel connector for second stage regulators.
2. Background Art
Scuba regulators utilizing ball swivels have been available for some time. The problem with current ball swivel designs is the O-ring sealing reliability and the effects of that reliability on product safety. In prior art designs the swivel ball is made from metal, “mostly chromed plated brass”. This is a very cost-effective means to produce the ball. However, due to the effects of corrosion, the ball suffers from reliability problems. Current ball swivel designs allow seawater to leak into the O-ring sealing areas. When seawater is trapped inside the sealing area it will corrode the swivel ball. Once the swivel ball starts to corrode, the chromed surfaces degrade rapidly. The end result is the pressure sealing O-ring is often cut or abraded allowing system pressure to leak out. This is a safety concern. One could make the swivel ball from a material that will not corrode using various non-corrosive plating or machining the ball from expensive alloys such as titanium. These are effective solutions, but costly.
Another problem with the prior art design is it makes no provision to contain O-ring lubrication. Once the sealing O-ring becomes dry of lubrication, the metal swivel ball will tend to bind or require greater effort to rotate due to friction. In addition, the prior art design allows saltwater and fine sand to enter the system. This can scratch the metal ball and over time will degrade the O-ring. A better swivel ball sealing design is needed.
Applicant herein has addressed these problems with the swivel connector disclosed in U.S. Pat. No. 7,188,869. In the low-pressure ball swivel design of the '869 patent, the ball is made from a metal with good corrosion resistance. The ball is then held into a true position by two separate low friction bushings. The two bushings, “sandwich” the metal swivel ball with light assembly pressure. This is accomplished by machining or molding the same radius of the swivel ball into one side of each of the two low friction bushings. Thus the ball is held in position with extreme precision. The bushing could be machined or molded from many low friction plastics or internal lubricated materials.
Because the '869 patent discloses a stainless steel or titanium ball that rotates axially in a 30 degree range of motion, a pressurized condition, creates higher coefficient of friction between the metal swivel ball and O-ring. Also, when the O-ring is “sandwiched” or squeezed between two low friction bushings under light assembly pressure, even more friction is added to the metal ball and O-ring contact. Further, the overall design has manufacturing difficulty and would have better durability if the O-ring could be located in such a way as to expel debris before it could become impacted into the seawater side of the assembly.